Vehicle transmission gear



Judy/31,1923. 11,463,?28

P. D. SINCLAIR VEHICLE TRANSMISSION GEAR Filed June 15 1921 l a'tente-dduly fill, i923 PETER D. SINCLAIR, OF MARION, NORTH CAROLINA.

VEHICLE TRANSMISSION GEAR.

Application filed June 15, 1921.

T all whom 2'5 may concern:

Be it known that PETER D. SINCLAIR, a citizen of the United States ofAmerica, residing at Marion, in the county of Mc- Dowell and State ofNorth Carolina, has invented new and useful Improvements in VehicleTransmission Gears, of which the following is a specification.

The object of the invention is to provide a simple and efficienttransmission gear for vehicles of the truck tractor and similar typespreferably as an interchangeable or selected means of communicatingmotion. from the motor to the traction wheels and adapted for use onparticularly heavy or loose surfaced roads; and with this object in viewthe invention consists in a construction and combination of parts ofwhich a preferred embodiment is shown in the accompanying drawings,wherein Figure 1 is a side view of a transmission gear embodying theinvention applied in the operative position to a vehicle of which aportion is shown in outline.

Figure 2 is a plan view of the same.

Figure u is a detail sectional view on the plane indicated by the line83 of Figure l.

The transmission gear embodying the invention includes a traction unit10 consisting of an endless chain having an inner surface conforming tothe tread 1]. of a traction wheel 12 having either a pneumatic orcushion tire, said traction unit being provided exteriorly if desiredwith suitable spaced spurs 13 and being extended around drive sprocket14- carried by a differential counter-shaft 15 disposed for example inperpendicularity with the motor shaft 16 and adapted to receive motiontherefrom through the intermeshing gears 1? and18. The motor indicatedat 19 is adapted as in the ordinary practice to communicate motion tothe drive shaft 20 extending as in the ordinary practice to thedifferential gear on the rear axle, but in order that the motor mayserve to drive the traction wheels either in the ordinary way throughthe drive shaft 20 or through the transmission mechanism embodying thisinvention, the gear 17 is keyed upon the motor shaft 16 and carries aSerial No. 477,720.

clutch face as indicated, for engagement with a complemental clutch face22 on a coupling 23 carried by the drive shaft 20, suitable shiftingmechanism consisting of a lever 2 1- and a grooved collar 25 beingemployed to enable the operator to adjust the parts as the conditions ofoperation of the truck or tractor may require. When the clutch member 17is shifted to interlock with the member 22 and thus communicate motionfrom the motor directly to the drive shaft 20 the gear 17 is disengagedfrom the gear 18, whereas when the lever 24- is reversed in position todisengage the drive shaft 20 motion is communicated from the motor shaftdirectly through the gear 18 to the countershaft 15 for actuating theendless chain constituting the traction unit. @b viously the chain 10should be provided with a removable pin 26 to permit of disengaging theends of the same for removal when not required and a suitable chaintightener 27 may be employed to ensure a proper frictional engagement ofthe traction unit with the tread of the traction wheel 12.

Having described the invention, what is claimec as new and useful is Thecombination with a vehicle having driving wheels, a transmission shaftcom municating motion thereto and a driving" motor, of a differentialcountershaft carried by the vehicle, and having sprockets on itsextremities, endless traction elements engaged with the driving wheelsand with the sprockets, clutch interposed between the transmission shaftand the motor, a pinion carried by one of the elements of said clutch, apinion operatively connected with the differential countershaft, andmeans for opcrating the pinion carrying; the clutch element to move ittoward and away from the complemental element whereby when the clutchelements are engaged the pinion is moved laterally to mesh with thepinion connected with the countershaft, reengagement of the pinionsbeing effected by the disengagement of the clutch elements.

In testimony whereof he afliXes his signature.

PETER D. SINCLAIR.

